Fuel injection pumps having a rotating distributing valve



June 6, 1967 J. R. GERAUDON 3,323,505

FUEL INJECTION PUMPS HAVING A ROTATING DISTRIBUTING VALVE Filed Dec. 15,1964 2 Sheets-Sheet l J MMEMRQMOJ ATTURNEK June 6, 1967 J. R. mRAuDoNFUEL INJECTION PUMPS HAVING A ROTATING DISTRIBUTING VALVE Filed Dec. 15,1964 2 Sheets-Sheet 2 ATTORNEE United States Patent 3,323,565 FUELINJECTION PUIMWS HAVING A ROTATWG DTSTRIBUTHNG VALVE Jean Ren *Giraudon,Paris, France, assignor to Societe Industrielle Generals de MecaniqueAppliquee S.I.G.M.A., Paris, France Filed Dec, 115, 1964, Ser. No.418,410 Claims priority, application France, Dec. 19, 1963,

' ,848 3 Claims. (Cl. 1Z3--139) The present invention relates to a fuelinjection pump for a multicylinder internal combustion engine, said pumpcomprising a fixed body and, inside said fixed body a rotatingdistributing valve driven by a shaft itself driven by the engine andsubstantially coaxial with said distributing valve, such a pump furthercomprising at least a pump piston reciprocable, in a bore provided inone of the two elements constituted by the fixed body and the drivingshaft, under the action of a cam carried by the other of said twoelements, the fixed body being provided with distribution conduitsleading to the engine injectors and cooperating with distributionpassages carried by the rotating distributing valve and adapted tocommunicate with said bore. The invention is more especially, but notexclusively, concerned with pumps of this type wherein the distributingvalve is arranged in such manner as to reduce the rate of delivery ofthe pump when said rotary valve is given a translatory movement andwherein a centrifugal regulating device responsive to the speed ofrevolution of the engine is adapted to control this distributing valve,with respect to its driving shaft, first in rotation (variation of theadvance to injection) then in translation (variation of the rate ofinjection) in response to variations of the speed of the internalcombustion engine.

The object of the present invention is to provide a pump of this kindwhich is better adapted to meet the requirements of practice than thoseexisting at the present time concerning the construction of the jointinterposed between the internal combustion driving shaft and thedistributing valve of the pump.

According to the present invention, said joint comprises a drivingelement consisting of a first sleeve rotating together with the drivingshaft, a driven element consisting of a cup-shaped member rotatingtogether with the distributing valve and an intermediate sleeveinterposed between said first sleeve and said cup-shaped member theadjoining edges of the first sleeve and of the intermediate sleeve,respectively, being interlocked by means of cooperating sets of teethdisposed circularly with a first angular interval from one tooth to thenext one whereas the adjoining edges of the intermediate sleeve and ofthe cup-shaped member, respectively, are interlocked by means ofcooperating sets of teeth disposed circularly with a second angularinterval from one tooth to the next one, said interval being differentfrom the first mentioned interval, which permits of adjusting theangular position of the driving member with respect to the distributingvalve by varying the relative setting of the teeth engaged together, themeans for transforming the translatory movement of the distributingvalve into a movement of rotation thereof with respect to the drivingshaft being advantageously interposed between said shaft and saiddriving member.

A preferred embodiment of the present invention will be hereinafterdescribed with reference to the appended drawings, given merely by wayof example, and in which:

FIG, 1 is an axial sectional view of a fuel injection pump madeaccording to the present invention;

FIG. 2 is a sectional partial view on the line II-Il of FIG. 1;

3,323,505 Ratented June 6, 1967 FIG. 3 is a cross sectional view on theline III-4H of FIG. 1;

FIG. 4- is a cross sectional view on the line IV-IV of FIG. 1.

FIG. 5 shows, on an enlarged scale, a modification of a detail of FIG.1, the elements being shown separately.

The fuel injection pump illustrated by the drawings comprises a fixedbody 1, preferably made of two coaxial pieces la and 1b, and adistributing valve 2 rotating in a cylindrical bore 3 provided in bodyll, said valve 2 being driven in rotation by a shaft 4 itself driven bythe internal combustion engine (not shown by the drawings) fed with fuelby the pump.

Two opposed pump pistons 5, only one of which is illustrated by thedrawings (FIG. 2 thereof), are slidable, in respective cylinders 6substantially perpendicular to the common axis of distributing valve 2and shaft 4, under the action of an annular cam '7 including as manyinward projections as the internal combustion engine comprises cylindersto be fed successively with fuel.

Cylinders 6 are placed in communication with the injectors of theinternal combustion engine through conduits 8 provided in body 1.Annular cam 7, carried by a disc-shaped portion 4a integral with drivingshaft 4, gives pistons 5' their reciprocating radial movements incylinders 6 through rollers 9 and push-pieces 10, against the action ofreturn springs 11. Cam 7 is journalled, through a bearing 12, in acasing 13 through the end wall of which shaft 4 extends, with theinterposition of packing means 14, said end wall carrying a thrust ballbearing 15 for shaft 4-.

In order to feed fuel to cylinders 6, there is provided in casing 13 afeed pump .16 the suction of which communicates with an inlet connection17., The delivery of this pump 16 communicates through a pipe 18 with aconnection 20 adapted in a removable manner to casing 13. Thisconnection is in permanent communication, through a conduit 21 and anannular groove 22 provided in body 1, with equidistant radial holes 23,the number of which is equal to the number of the internal combustionengine cylinders, which holes 23 open into bore 3 opposite a firstlongitudinal groove (not visible on the drawings) provided indistributing valve 2, this first longitudinal groove opens into aperipheral annular groove 24 provided in distributing valve 2 and inpermanent communication with pump cylinders 6.

The delivery circuit from said pump cylinders 6 comprises a secondlongitudinal groove 25 starting from annular groove 24 and leading todelivery passages 8.

It will be understood that fuel injection begins when a hole '23 ceasesto be in communication with the second longitudinal groove 25 and thatit is cut off just when the next hole 23 is placed in communication withthe first longitudinal groove.

There is provided a regulating device capable of varying the angular andlongitudinal positions of distributing valve 2 with respect to drivingshaft 4.

Variation of the angular position of said distributing valve 2 withrespect to shaft 4 offsets, in the cycle of operation, the period forwhich no radial hole 23 communicates with both of the longitudinalgrooves of distributing valve 2 that is to say varies the advance toinjection, whereas variation of the longitudinal position ofdistributing valve 2 varies the flow rate of the pump per revolution ifsaid longitudinal grooves are provided with inclined portions, such as25a, oblique in opposed directions with respect to the axis ofdistributing valve 2 and located opposite radial holes 23.

For this purpose, there is provided a regulating device capable ofexerting an axial force, variable in the same manner as the speed ofrotation of shaft 4, upon a cylindrical member 26 capable of slidingwithout rotating with respect to shaft 4, against the action of a spring27, while imparting a helical movement to distributing valve 2 throughmeans which will be hereinafter described. This member 26 is subjected,on the one hand, to the action of said force, and on the other hand, inthe opposed direction, to the action of return means adjustable througha forked lever 35.

The regulating device comprises two masses 28 pivoted about tworespective axes 29 carried by an annular projection 4b of shaft 4, eachof said masses 28 carrying an arm 30 (FIG. 4), which will be hereinafterreferred to, and which serves to produce, through a spindle 31, .alongitudinal movement of member 26 serving to control distributing valve2, against the action of spring 27.

With such a regulating device the angular position of distributing valve2 with respect to shaft 4 will depend upon the force exerted by masses28, this force depending itself upon the speed of revolution of theinternal combustion engine. Furthermore, the axial position ofdistributing valve 2 with respect to shaft 4 will depend not only onsaid force but also on the position of lever 35.

Preferably, as shown, the return means above referred to consists of aset of springs 33 the end of which opposed to that connected todistributing valve 2 bears upon a cup-shaped member 34 movable inresponse to the movements of the throttle valve of the internalcombustion engine, for instance by the provision of forked lever 4-5fixed on the spindle 36 of the throttle valve. As for the other end ofthis set of springs 33, it acts upon distributing valve 2 through aresilient plate 37 carried by a lever 38 pivoted about an axis 3-) andinterposed between distributing valve 2 and the set of springs 37.

Such a pump works as follows:

When shaft 4 revolves together with cam 7, pistons are alternatelypushed outwardly (suction) under the action of springs 11 and inwardly(delivery) when rollers 9 run along the bosses of cam 7. During thesuction periods, the fuel under pressure in annular groove 22 passesthrough holes 23, located opposite the longitudinal grooves ofdistributing valve 2 and said fuel comes to fill up the volumesresulting from the outward movements of pistons 5 in cylinders 6. Duringthe delivery periods, fuel is delivered into annular groove 24 and thelongitudinal grooves of the distributing valve. As long as one of theholes 23 is cleared by longitudinal groove 25, fuel is dischargedthrough this hole into annular groove 22 and there is no injection. Assoon as distributing valve 2, which rotates at the same speed as cam 7,has covered this hole by its inclined groove a, the fuel delivered bypistons 5 passes through groove 25 and through that of passages 8 whichis located opposite this last mentionel groove and thus reaches thecorresponding engine injector. Thus injection takes place until theother longitudinal groove of distributing valve 2, the inclined portionof which is inclined in a direction opposed to that of inclined portion25a, clears the next hole 23. Therefore the inclined portions related tothe two longitudinal grooves of the distributing valve determine thebeginning and the end of injection respectively, the regulating devicedetermining the beginning of injection in every cycle of the pump andthe rate of injection of the pump.

In order to have the delivery rate of the pump uninfluenced byvariations of the advance to injection, pistons 7 must move with aconstant velocity for a constant speed of revolution of cam 7.

The object of the present invention is to permit an adjustment of theangular position of distributing valve 2 with respect to cam 7 suchthat, within the limits of said adjustment, injection always takes placefor a displacement of pistons 5 within which, for all possible speeds ofrevolution of the internal combustion engine, the velocity of movementof said pistons 5 depends only upon said engine speed.

For this purpose, according to the present invention the jointinterposed between cylindrical member 26 and distributing valve 2comprises a driving element consisting of a sleeve 4ft revolvingtogether with shaft 4, a driven element consisting of a cup-shapedmember 41 fixed with respect to distributing valve 2, and anintermediate sleeve between said first sleeve 40 and said cupshapedmember 41, the adjoining faces of sleeve 40 and of intermediate sleeve42 carrying cooperating teeth 43 forming a circular row with a firstangular interval between them, whereas the adjoining faces ofintermediate sleeve 42 and cup-shaped member 41 carry c0- operatingteeth 44 forming another circular row with a second angular intervalbetween said last mentioned teeth different from the above mentionedinterval.

Cylindrical member 26 is provided with two longitudinal ribs 26aslidable, respectively, in two grooves provided in shaft 4 and parallelto the axis of said shaft whereby member 26 can slide without rotatingwith respect to shaft 4. In order to transform the translatory movementof distributing valve 2 produced by the regulating device into amovement of rotation about the axis of shaft 4, two lugs 40a areprovided on sleeve 40 and slidably engaged in two helical grooves 45provided in member 26. Finally in order to secure the whole of sleeve 40and of intermediate sleeve 42 to distributing valve 2, the end of saidvalve 2 carries a threaded rod 46 on which is mounted a nut 47 appliedagainst the end wall of sleeve 40. Cup-shaped member 41 is fixed, forinstance by welding, to distributing valve 2. A spring 27, freelysurrounding sleeve 40 and intermediate sleeve 42, bears at one endagainst piece 26 and at the other end against cup-shaped member 41.

According to the embodiment of FIG. 1, the sets of teeth 43 and 44 areprovided on the whole periphery of elements 40, 41, and 42. Therespective numbers of the teeth of these sets of teeth (which teethadvantageously consist of ribs), preferably differ by one. For instancethese numbers are 24 for set 43 and 25 for set 44.

According to the modification of FIG. 5, where the first mentionedsleeve is designated by 4%, the cupshaped member by 4111 and theintermediate sleeve by 42b, there are only two teeth or projections,respectively 43:: and 44a upon sleeve 4% and cup-shaped member 41b,whereas notches 43b and 44b, formed in intermediate sleeve 42b, extendover portions only of the periphery of said sleeve 42b, symmetricalrespectively with respect to each other. Ribs 43]) are at 15 from oneanother and ribs 44]) are at 16 from one another.

The joint thus obtained permits, after loosening of nut 4-7, ofadjusting the angular position of distributing valve 2 with respect toshaft 4 with a very high accuracy, by a suitable choice of the hollowsand teeth 43, 44 or 43a, 43b, 44a, 44b engaged in one another. In thenumerical examples above stated, in the case of FIG. 1 the adjustment iseffected by steps corresponding to multiples of an angle equal to thedifference between 360/24 and 360/25, that is to say by stepscorresponding to three fifth of a degree whereas in the constructionaccording to FIG. 5 the adjustment is effected by steps corresponding toone degree.

In a general manner, while the above description discloses what isdeemed to be a practical and efficient embodiment of the presentinvention, said invention is not limited thereto as there might bechanges made in the arrangement, disposition and form of the partswithout departing from the principle of the invention as comprehendedwithin the scope of the appended claims.

What I claim is:

1. For use in connection with an internal combustion engine, a fuelinjection pump for said engine which comprises, in combination,

a fixed body,

a driving shaft operative by said internal combustion engine androtatable in said body about an axis, said shaft being provided with anaxial cylindrical recess in the wall of which are formed two groovesparallel to the shaft axis,

one of the two above mentioned parts being provided with at least onebore radial with respect to said axis,

a piston slidable in said bore,

a cam rigid with the other of said two first mentioned parts operativelyconnected with said piston for controlling the reciprocating movementthereof in response to the rotation of said two parts with respect toeach other,

a distributing valve rotatable in said body and substantially in linewith said shaft,

said distributing valve being provided with distribution passagesadapted to communicate with said bore,

said fixed body being provided with fuel distributing conduits adaptedto communicate with said distribution passages,

a joint for coupling together said shaft and said distributing valve,aid joint including,

a driving structurecomprising a cylindrical member provided, externally,with two longitudinal ribs slidable, respectively, in said grooves,whereby said cylindrical member can slide without rotating with respectto said shaft, said cylindrical member being provided in its inner facewith two helical grooves, and a first sleeve coaxially disposed in saidcylindrical member and including two external lugs slidable in saidhelical grooves,

a driven element consisting of a cup-shaped member rigidly fixed to saiddistributing valve,

an intermediate sleeve interposed between said first sleeve and saidcup-shaped member coaxially therewith,

two cooperating sets of teeth disposed circularly along the adjoiningedges of the first sleeve and of the intermediate sleeve, respectively,with a first angular interval from. one tooth to the next one, forinterlocking said first sleeve and said intermediate sleeve together,and

two cooperating sets of teeth disposed circularly along the adjoiningedges of the intermediate sleeve and of the cup-shaped member,respectively, with a second angular interval from one tooth to the nextone, for interlocking said intermediate sleeve and said cup-shapedmember together, said second interval being dilferent from the firstmentioned interval,

whereby the angular position of said driving shaft with respect to thedistributing valve can be adjusted by varying the relative setting ofthe teeth engaged together, and

means, between said driving shaft and said driven sleeve, fortransforming the translatory movement of said distributing valve into amovement of rotation with respect to said shaft.

2. A fuel injection pump according to claim 1 wherein the sets of teethextend along the whole edge of said first sleeve, of said intermediatesleeve and of said cup-V shaped member.

3 A fuel injection pump according to claim 1 wherein only two teeth orprojections are provided on the first sleeve and on the cup-shapedmember, whereas notches formed in the intermediate sleeve extend overportions only of the periphery of said intermediate sleeve.

References Cited UNITED STATES PATENTS 2,906,106 9/1959 Haas 64-93,091,231 5/1963 Giraudon 123-140 FOREIGN PATENTS 507,602 6/ 1920France.

MARK NEWMAN, Primary Examiner. LAURENCE M. GOODRIDGE, Examiner.

1. FOR USE IN CONNECTION WITH AN INTERNAL COMBUSTION ENGINE, A FUELINJECTION PUMP FOR SAID ENGINE WHICH COMPRISES, IN COMBINATION, A FIXEDBODY, A DRIVING SHAFT OPERATIVE BY SAID INTERNAL COMBUSTION ENGINE ANDROTATABLE IN SAID BODY ABOUT AN AXIS, SAID SHAFT BEING PROVIDED WITH ANAXIAL CYLINDRICAL RECESS IN THE WALL OF WHICH ARE FORMED TWO GROOVESPARALLEL TO THE SHAFT AXIS, ONE OF THE TWO ABOVE MENTIONED PARTS BEINGPROVIDED WITH AT LEAST ONE BORE RADIAL WITH RESPECT TO SAID AXIS, APISTON SLIDABLE IN SAID BORE, A CAM RIGID WITH THE OTHER OF SAID TWOFIRST MENTIONED PARTS OPERATIVELY CONNECTED WITH SAID PISTON FORCONTROLLING THE RECIPROCATING MOVEMENT THEREOF IN RESPONSE TO THEROTATION OF SAID TWO PARTS WITH RESPECT TO EACH OTHER, A DISTRIBUTINGVALVE ROTATABLE IN SAID BODY AND SUBSTANTIALLY IN LINE WITH SAID SHAFT,SAID DISTRIBUTING VALVE BEING PROVIDED WITH DISTRIBUTION PASSAGESADAPTED TO COMMUNICATE WITH SAID BORE, SAID FIXED BODY BEING PROVIDEDWITH FUEL DISTRIBUTING CONDUITS ADAPTED TO COMMUNICATE WITH SAIDDISTRIBUTION PASSAGES, A JOINT FOR COUPLING TOGETHER SAID SHAFT AND SAIDDISTRIBUTING VALVE, SAID JOINT INCLUDING, A DRIVING STRUCTURE COMPRISINGA CYLINDRICAL MEMBER PROVIDED, EXTERNALLY, WITH TWO LONGITUDINAL RIBSSLIDABLE, RESPECTIVELY, IN SAID GROOVES, WHEREBY SAID CYLINDRICAL MEMBERCAN SLIDE WITHOUT ROTATING WITH RESPECT TO SAID SHAFT, SAID CYLINDRICALMEMBER BEING PROVIDED IN ITS INNER FACE WITH TWO HELICAL GROOVES, AND AFIRST SLEEVE COAXIALLY DISPOSED IN SAID CYLINDRICAL MEMBER AND INCLUDINGTWO EXTERNAL LUGS SLIDABLE IN SAID HELICAL GROOVES, A DRIVEN ELEMENTCONSISTING OF A CUP-SHAPED MEMBER RIGIDLY FIXED TO SAID DISTRIBUTINGVALVE, AN INTERMEDIATE SLEEVE INTERPOSED BETWEEN SAID FIRST SLEEVE ANDSAID CUP-SHAPED MEMBER COAXIALLY THEREWITH, TWO COOPERATING SETS OFTEETH DISPOSED CIRCULARLY ALONG THE ADJOINING EDGES OF THE FIRST SLEEVEAND OF THE INTERMEDIATE SLEEVE, RESPECTIVELY, WITH A FIRST ANGULARINTERVAL FROM ONE TOOTH TO THE NEXT ONE, FOR INTERLOCKING SAID FIRSTSLEEVE AND SAID INTERMEDIATE SLEEVE TOGETHER, AND TWO COOPERATING SETSOF TEETH DISPOSED CIRCULARLY ALONG THE ADJOINING EDGES OF THEINTERMEDIATE SLEEVE AND OF THE CUP-SHAPED MEMBER, RESPECTIVELY, WITH ASECOND ANGULAR INTERVAL FROM ONE TOOTH TO THE NEXT ONE, FOR INTERLOCKINGSAID INTERMEDIATE SLEEVE AND SAID CUP-SHAPED MEMBER TOGETHER, SAIDSECOND INTERVAL BEING DIFFERENT FROM THE FIRST MENTIONED INTERVAL,WHEREBY THE ANGULAR POSITION OF SAID DRIVING SHAFT WITH RESPECT TO THEDISTRIBUTING VALVE CAN BE ADJUSTED BY VARYING THE RELATIVE SETTING OFTHE TEETH ENGAGED TOGETHER, AND MEANS, BETWEEN SAID DRIVING SHAFT ANDSAID DRIVEN SLEEVE, FOR TRANSFORMING THE TRANSLATORY MOVEMENT OF SAIDDISTRIBUTING VALVE INTO A MOVEMENT OF ROTATION WITH RESPECT TO SAIDSHAFT.